Rolled eraser and holder



1366- 1965 KWONG LI LOU ROLLED ERASER AND HOLDER Filed July 17, 1964 K! 474 Y! /i Zia /d 20 United States Patent 3,224,416 ROLLED ERASER AND HGLDER Kwong Li Lou, Civil Air Transport Inspection Dept, Tainan Airfield, Tainan, Taiwan, China Filed July 17, 1964, Ser. No. 383,358 8 Claims. (Cl. 120-36) This invention relates to erasers, and more particularly to an eraser rolled in spiral form and disposed in a holder, so as to form an eraser strip which emerges from the holder.

It has been found that sharp edges in an eraser are more useful in erasing than flat surfaces, particularly with respect to erasing small areas. In conventional erasers, after a short period of use, the eraser edge tends to become worn away, so that a broad or fiat eraser surface is formed, thus making difficult the accurate erasure of a small area. Furthermore, as a result of the flat eraser surface, a large proportion of the eraser material is wasted in use by such conventional erasers, since the actual surface being erased greatly exceeds the surface required to be erased.

According to the present invention, a disk-shaped eraser having a cut extending partially therethrough and spiralling outwardly from the center thereof is disposed within a holder having an eraser strip outlet, so that the outermost portion of the eraser spiral, when cut into a strip, passes through the outlet and is available for use as an erasing medium. Cutting and guide means are attached to the eraser holder, preferably adjacent the outlet, to complete the cutting through of the eraser along the spiral cut and to guide the thin eraser strip formed thereby into the outlet. The eraser is connected to the holder by means of a pivotal holder arm, which normally urges the eraser into the holder. In the preferred embodiment, the outlet is inclined with respect to the eraser proper, so as to provide frictional resistance against retraction of the eraser strip during erasing, and a roller is pivotally attached to the holder so as to contact the eraser to provide a feed control of eraser strip into the outlet.

The invention may be more readily understood by referring to the accompanying drawing, in which:

FIGURE 1 is a front elevation of an eraser holder according to the invention;

FIGURE 2 is a view, in section, taken along lines 2-2 of FIGURE 1;

FIGURE 3 is a front elevation, similar to FIGURE 1, and showing an eraser attached to the holder but not in position for use;

FIGURE 4 is a side elevation taken along lines 4-4 of FIGURE 1;

FIGURE 5 is a front elevation, similar to FIGURE 3, but showing the eraser and holder of the invention in position for use;

FIGURE 6 is a side elevation taken along lines 66 of FIGURE 5;

FIGURE 7 is a view, partially in section, taken along lines 77 of FIGURE 3;

FIGURE 8 is a view, in section, taken along lines 88 of FIGURE 5;

FIGURE 9 is a view, in section, taken along lines 99 of FIGURE 6;

FIGURE 10 is a view, in section, taken along lines 1010 of FIGURE 3; and

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FIGURE 11 is a partial sectional view taken along lines 1111 of FIGURE 3.

Referring initially to FIGURE 1, an eraser holder according to the invention has a back plate 12 and a front plate 12a connected together by an arcuate bottom plate 12b (not shown, see FIGURE 4). An eraser holder arm 13 having a pin 14 passing through a lateral relative movement slot 15 in the arm 13 is utilized to connect an eraser to the eraser holder. A roller 16 (shown in detail in FIGURES 10 and 11) is utilized to control the movement of the eraser through an eraser strip outlet 17, as will be subsequently explained. A diametrical positioning slot 18, formed in the front plate 12a, permits the pin 14 to move relative to the outlet 17 so as to force a disk-shaped eraser 19 (see FIGURES 3 and 9) against the roller 16. By manually rotating the roller 16, the feeding of eraser material through the outlet 17 is controlled, as will be subsequently explained.

It will be noted that the diametrical slot 18 is straight, rather than arcuate, so that the pin 14 moves laterally, relative to the eraser holder arm 13, in the slot 15 as the pin 14 moves in the diametrical slot 18 toward or away from the outlet 17. The diametrical slot 18 is, thus, disposed so as to be substantially tangential to an are described by the pin 14 upon pivotal movement of the eraser holder arm 13.

The disk-shaped eraser 19 is shown in FIGURES 8 and 9 as formed by a fiat disk of eraser material partially cut through by a cut spiralling outwardly from its center and having an eraser strip or end 19:: projecting from the outlet 17. The eraser 19 is urged against the roller 16 by the eraser holder arm 13, as will be subsequently explained. A pin 21), having a body portion 20, passes through the roller 16 and acts as an axle so that the roller 16 may be rotated to feed, by friction, the eraser material through the outlet 17 The eraser 19 is mounted on the body portion 21 of the pin 14, so as to be rotatable. A spring 22, preferably of the coil spring type, is contained in a spring holder 23 and attached to a pin 24. The pin 24 is also attached to the arm 13 so that the coil spring 22 tends to urge the arm 13 in a counter-clockwise direction, as seen in FIGURES l and 3, urging the pin 14 to ride in the diametrical slot 18. Formed in the eraser holder adjacent the eraser strip outlet 17 is a cutting and guide assembly 25 for cutting through the eraser along the spiral cut and directing the thin strip of eraser material so formed into the outlet 17. In the preferred embodiment, the blade assembly 25 has a blade edge 25a and a blade guide 25b. The blade edge 25a cuts through the uncut portion of the eraser spiral out while the guide 25b guides the uncut portion against the blade 25a. The cut portion or strip of the eraser, which is guided through the outlet 17, forms an eraser end or strip 19a. The eraser 19 is connected to the pin body portion 21 by means of a bushing 26, so as to be freely rotatable with respect to the pin 14.

In the preferred embodiment, the eraser 19 is partially cut in a spiral configuration, as will be apparent from FIGURE 8. In order to attach the eraser to the eraser holder, the arm 13 is moved so as to remove the pin body portion 21 from the diametrical slot 18, the arm 13 and pin 14 assuming the position shown in dotted lines in FIGURE 1. The eraser 19 is then attached to the pin body portion 21 by means of the bushing 26, the eraser 19 then being in the position shown in FIG- URES 3 and 7. Under the urging of the coil spring 22, the arm 13 moves counterclockwise so as to dispose the pin body portion 21 within the diametrical slot 18, as is shown in FIGURES 5 and 9. The eraser 19 is then rotated clockwise, so as to cause the blade assembly 25 to cut a Strip 19a of eraser material from the eraser 19 and guide the strip through the outlet 17. The eraser 19 is urged against the roller 16 by the coil spring 22 acting on the eraser holder arm 13. Thus, the eraser 19 may be rotated by rotating the roller 16, and thereby cut the strip 19a from the eraser 19. If desired, however, the open portion of the eraser 19 adjacent the semi-circular front plate 12a may be rotated by direct pressure, rather than by relying on the roller 16, so as to cut the strip 19a. When utilizing the roller 16, it is preferable to also assist in urging the eraser 19 against the roller 16 by manually pressing on the pin 14.

It will be noted that the outlet 17, as is shown in FIGURES 2, 4, 6, and 8, is laterally inclined with respect to the plates 12, 12a. During the act of erasing, preferably, the back plate 12 faces the user while the front plate 12a faces away from the user. For example, the back plate 12 is held by the thumb and the front plate 12a by the index finger and middle finger. Of course, the opposite disposition is also utilizable. As a result of the inclination of the outlet 17, the eraser end 19a is readily visible to the user while erasing. Thus, erasing can be done accurately at the desired spot. The size of the outlet 17 is selected with respect to the size of the eraser strip 19a, which may be square or half round, in order to permit the eraser strip 19a to pass smoothly therethrough.

As is shown in FIGURES 2, 4, 6, and 8, the outlet 17 is inclined in the direction of the back plate 12. However, the outlet 17 can be inclined in the direction of the front plate 12a, if desired, in which case, preferably, the thumb will contact the front plate 12a and the index finger the back plate 12. In either embodiment, it is preferable to have the digit contacting the front plate 12a rest against the pin 14 so as to insure the urging of the eraser 19 against the roller 16. The eraser is thereby fixed securely with respect to the holder and the eraser end 19a prevented from being forced back into the holder by the erasing pressure exerted by the user.

As the eraser end 19a is gradually worn away, the eraser 19 is rotated clockwise so as to force additional eraser material through the outlet 17. As eraser 19 is used up, its diameter becomes smaller, so that the spring 22, by urging the arm 13 in a counter-clockwise direction, moves the eraser 19 along the slot 18 toward the outlet 17 and maintains contact between the eraser 19 and roller 16. Thus, the pin 14 gradually moves along the slot 15 away from the spring 22 as the arm 13 pivots counter-clockwise in moving the eraser 19 toward the outlet 17. Therefore, the eraser 19, in spite of the gradual reduction in diameter, always contacts the roller 16, so that rotation of the roller 16 will always provide additional material at the eraser end 19a.

The bushing 26 and mounting stud 21 may be any desired cross sectional configuration, such as a square, rather than circular, if desired. In using a square or similar configuration, the eraser 19 may be rotated by rotating the pin 14, rather than by utilizing the roller 16. If desired, a knob is attached to the pin body portion 21 in such an embodiment to facilitate rotation.

By utilizing a configuration for the eraser 19 such as a spiral which is partially cut through, the eraser 19 is held together when rotated, while permitting an even cutting of the eraser strip to provide a constant cross sectional configuration of the eraser end 19a.

As will be readily apparent, the relative disposition of the various components of the invention may be reversed, if desired. In such an embodiment, the roller 16 is disposed on the opposite side of the blade assembly 25 from that shown in FIGURE 9, and the blade assembly 25 rotated one hundred and eighty degrees, so as to provide an appropriate cutting and guiding surface. The arm 13 is then mounted so as to be urged clockwise rather than counter-clockwise by the coil spring 22 to move the pin body portion 21 into the slot 18. Thus, the use of terms such as clockwise are for the purpose of explanation rather than limitation, and are to be so interpreted.

I claim:

1. In an eraser apparatus, the combination of:

an eraser of generally disk-shaped configuration and having a cut extending partially therethrough spiralling outwardly from the center thereof;

an eraser holder having a back plate, a front plate, and

a bottom plate connecting the front and back plates so as to form an eraser enclosure;

an eraser holder arm;

means pivotally connecting the eraser to the eraser holder arm so that the eraser is rotatable with respect thereto;

means pivotally attaching the eraser holder arm to the eraser holder so that the eraser holder arm normally urges the eraser into the eraser enclosure;

an eraser strip outlet formed in the eraser holder; and

eraser cutting and guide means attached to the eraser holder for cutting through the eraser along the spiral cut so as to cut a strip of eraser material therefrom and for guiding said strip into said eraser strip outlet.

2. The combination of claim 1, and in which:

the back plate is generally circular in configuration;

the front plate (a) is generally semi-circular in configuration, and (b) has a diametrical slot formed therein so as to extend toward the bottom plate generally tangential to an arc which is described by movement of the pivotal connection of the eraser to the eraser holder arm upon pivoting of the eraser holder arm so as to urge the eraser into the eraser enclosure; and,

the pivotal connection of the eraser to the eraser holder arm has means operable to permit limited lateral relative movement between the eraser and the eraser holder arm.

3. The combination of claim 1, and in which the holder has a roller rotatably fixed thereto so as to contact the eraser prior to cutting and a portion of which extends out of said holder.

4. The combination of claim 1, and in which the eraser strip outlet is generally tubular in configuration and is attached to the bottom plate so as to be laterally inclined with respect to the eraser.

5. The combination of claim 4, and in which:

the back plate is generally circular in configuration;

the front plate (a) is generally semi-circular in configuration, and (b) has a diametrical slot formed therein so as to extend toward the bottom plate generally tangential to an are which is described by movement of the pivotal connection of the eraser to the eraser holder arm upon pivoting of the eraser holder arm so as to urge the eraser into the eraser enclosure; and,

the pivotal connection of the eraser to the eraser holder arm has means operable to permit limited lateral relative movement between the eraser and the eraser holder arm.

6. The combination of claim 5, and in which the holder has a roller rotatably fixed thereto so as to contact the eraser prior to cutting and a portion of which extends out of said holder. T

7. The combination of claim 6, and in which the pivotal References Cited by the Examiner connection between the eraser and eraser holder arm con- UNITED STATES PATENTS sists of a pin extending through a slot formed in the eraser holder arm and through the center of the eraser, 413,798 10/1889 Young 120-36 and including a bushing at the eraser center through which 5 2 21 12/ 1940 Rudiger 12036 the pin extends so as to connect the eraser to the eraser FOREIGN PATENTS holder arm.

8. The combination of claim 7, and in Which the means 7 1 5 8 switlerland.

pivotally attaching the eraser holder to the eraser holder arm has a coil spring connected therebetween so as to 10 EUGENE CAPOZIO Prlmary Examme urge the pin into the diametrical slot in the front plate. LAWRENCE CHARLES, Assistant Examiner. 

1. IN AN ERASER APPARATUS, THE COMBINATION OF: AN ERASER OF GENERALLY DISK-SHAPED CONFIGURATION AND HAVING A CUT EXTENDING PARTIALLY THERETHROUGH SPIRALLING OUTWARDLY FROM THE CENTER THEREOF; AN ERASER HOLDER HAVING A BACK PLATE, A FRONT PLATE, AND A BOTTOM PLATE CONNECTING THE FRONT AND BACK PLATES SO AS TO FORM AN ERASER ENCLOSURE; AN ERASER HOLDER ARM; MEANS PIVOTALLY CONNECTING THE ERASER TO THE ERASER HOLDER ARM SO THAT THE ERASER IS ROTATABLE WITH RSPECT THERETO; MEANS PIVOTALLY ATTACHING THE ERASER HOLDER ARM TO THE ERASER HOLDER SO THAT THE ERASER HOLDER ARM NORMALLY URGES THE ERASER INTO THE ERASER ENCLOSURE; AN ERASER STRIP OUTLET FORMED IN THE ERASER HOLDER; AND ERASER CUTTING AND GUIDE MEANS ATTACHED TO THE ERASER HOLDER FOR CUTTING THROUGH THE ERASER ALONG THE SPIRAL CUT SO AS TO CUT A STRIP OF ERASER MATERIAL THEREFROM AND FOR GUIDING SAID STRIP INTO SAID ERASER STRIP OUTLET. 